concrete question

[southernbelle]

we want to build a basketball court about 30x35. I got an estimate from a contractor and he said that he did not have to use rebar or wire because the concrete had fiber in it. Does this make sense to anyone because I don't want to pay for this and have it crack all over the place?

 

[oldnslo]

we want to build a basketball court about 30x35. I got an estimate from a contractor and he said that he did not have to use rebar or wire because the concrete had fiber in it. Does this make sense to anyone because I don't want to pay for this and have it crack all over the place?

Do a search for concrete slabs. I found several articles explaining rebar Vs fiber Vs woven wire.

Roy

 

[Egon]

You might also want to check out "Portland Cement Association". All the information you want there if you look.

 

[tulenutn2o]

we want to build a basketball court about 30x35. I got an estimate from a contractor and he said that he did not have to use rebar or wire because the concrete had fiber in it. Does this make sense to anyone because I don't want to pay for this and have it crack all over the place?

Sounds like contractor wnats to take the easy way out. In other words, he doesn't like to put down rebar. Around here, everything is rebar or wire. Better contractors always specify rebar. Wire is bare minimum by code here. By the way: concrete is only guaranteed to do 2 things: 1) get hard (2) CRACK!:laughing:Key is to have it crack where you want it to, at the relief points.

 

[EddieWalker]

There are only two facts with concrete, it will get hard and it will crack.

The problem with concrete is that it moves on you. It expands and contracts. The size of the slab, mixture of materials and base underneith all figure into how big a monolithic slab you can go with minimal cracking.

Rebar works. It's proven technology, it's easy to use and it's stood up over the test of time. Wire mesh works, but it almost never done correctly. The most common way to do wire is to roll it out and then try to pull it into the center of the slab during the pour and while smoothing it out. I've heard stores of those who an do it, but in 100% of ever time I've seen it done, and seen pics of it posted on here, it just gets pushed to the bottom of the slab by the guys walking on it. I've cut into slabs with wire mesh and it's always at the bottom of the slab. If done properly, wire is extremly strong, problem is that it wont be done properly. Fiberglass adds strength to the concrete. Rumor has it that in some cases, it can replace rebar. For the price of reber, I would never take that gamble.

Fiberglass is cheap to add to your mix, but it's only a extra if you want it. Not something to rely on or to overcome other shortcomings in prep work.

The big negative to fiberglass is that it will poke out through the finished surface of the slab. In time, it will just wear away, so it's not that big of a deal.

Also remember that there are two types of concrete contractors. Those who do good work and those who don't. Check around, ask for refrences and if you have any doubts or concerns, walk away. It's one of those things that if done poorly, you will hate it forever. Pay what it costs to get it done right the first time and really think about what you are saving by going with the lowest bid.

Good luck,
Eddie

 

[dodge man]

I have a slab in front of my garage that was poured with no rebar or mesh, but it does have the fiber reinforcement in it. Its about 11 years old and so far so good. Eddie is correct on the mesh, more often than not it ends up in the bottom, even if the contractor makes an effort to keep it higher in the slab.

The key is to have a good stable base. Any concrete slab will move with the soil, even more so if you live in an area with frost heave. The key is to have the slab strong enough that it all moves the same amount together. If the subgrade is soft in an area, that part might settle and cause the slab to crack and settle more than other parts. Rebar can bridge this gap and keep it from cracking and settleing in an uneven manner. If the subgrade is in good shape, the fiberglass should work well.

 

[Car Doc]

Spend the money on steel and expansion joints now and enjoy your new pad for many many years and it will still be worth something then oh also it will crack sooner or later somewhere its a fact of life. jmho

Steve

 

[ray66v]

Forget about the poly concrete.

Put in the steel wire, and make sure it is properly pulled up into the wet concrete.

Make sure the concrete is divided to be grooved, or saw cut, into approximate SQUARES. Avoid rectangles, and any bizarre geometric patterns.

 

[beenthere]

I do both, and like the results. The fiber will have many minor cracks, and with enough movement, some all the way across. The wire is easy to put down and much better at holding it together. The extra cost/effort is minimal to having cracks and too late to do anything about them.

I also do not let the contractor get by with brooming the surface. They like to because it is less finish trowelling work for them. But the trowelling gets the surface worked out good and the stones/rock down below the surface. I much rather have a smooth surface that brooms/cleans easy compared to the rough broomed surface.

 

[Willl]

we want to build a basketball court about 30x35.

How 'bout asphalt instead ?